Fire control system



Jan. 18, 1944. CROOKE 2,339,461

FIRE CONTROL SYSTEM Filed May 15, 1940 3 Sheets-Sheet 1 v v INVENTOIIQ. ldwymondE. Croolce n- 1944- R. E. cRooKE FiRECONTROL SYSTEM 5 Sheets-Sheet 2 7 Filed May 15, 1940 INVENTOR. RqynwndECmoke ATTORNEY.

.Ja -la 1944. R. E. CROOKE FIRE- CONTROL SYSTEM Filed May 15, '1940 3 Sheets-Sheet 3 mvu mvaioJ.

v INVENTOR. v ondECrooJse ATTORNEY.

Patented Jan. 18, 1944 v I v [OFFICE v 2,339,461 FIRE CONTROL SYSTEM Raymond E.'Crooke, Great Neck, N. Y., assignor to Ford Instrument Company, Inc.,

land City, N. Y.

Long Isa corporation of New York Application May 15,1940, Serial No. 335.390 1 I scams. (01.8941) This invention relates to a 'fire control system and more particularly to a fire control system for a gun mounted for universal movement including traverse, that is, about an axis at right angles to the plane of elevation. 1

The principal object 01' 'the invention is to provide a director and a prediction computer particularly adapted to control the fire of universally mounted guns.

Another object of the invention is to provide a fire control system for a universally mounted gun that is mounted on a ship or a vehicle sub- Ject to rocking movements.

A further object oi. the invention is to provide a universally mounted sight on a ship or vehicle subjected to rocking movements, adapted, with other associated mechanisms, to control the fire of guns similarly mounted.

Other objects of the invention will become apparent from a consideration of the specification and drawings forming a part of this application and in which:

Fig. 1 is a perspective diagram of a director and gun mount of the invention in its simplest form; 1

Fig. 2 is a perspective diagi-am of the gun director in more detail and especially adapted to be used on an unstable platform; and

Fig. 3 is a schematic diagram of the arrange-,

ment shown in Fig. 2 and giving in detail the construction 01- theconverter for determining I the traverse correction.

andcomplicated as the changes in the settings for train distured the setting for elevation and vice versa. It was also diiilcult to provide a remote sight or director control for. mounts'of thistype. v

There have been remote sights that were universally mounted, such as described in Willard Patent No. 1,936,442, but in that arrangement the transmissions to the gun were in terms of the conventional train and elevation, whereas the transmissions in the present invention are in terms of train, elevation and traverse, which is a change in the angular position about an axis at right angles to the plane of thesight;

In the form of gun mount anddirector shown herein a target may be followed at or near the zenith as readily as at any other elevation as it will be seen that a combination of elevation and traverse will permitthe sight and the gun to 101- low a target in any'direction across the zenith and thereby obviate the need for excessive train corrections at these high elevations. sion of the traverse motion also makes it possible to readily move the sight and gun to compensate for rocking movement of the gun elevation'trunnions, the angle which the said trunnions assume relative tov the horizontal due to such movement being generally known as cross The standard time of gun mounts developed I for land and ship firing at surface targets and having only two axes of movement, viz., train and elevation, have been used at a disadvantage when firing at aerial targets and especially when these targets are at high angles of elevation. At these high angles of elevation it was impossible to follow a target as the training rate becomes excessively high when the target passes near the zenith.

lever or trunnion tflt. With the standard form of gun mount the training correction necessary to correct ior this trunnion tilt increases with the elevation and comes to exceed the amount of the trunnion tilt as the gun elevation becomes high. By making this correction as amovement in traverse, that is, a. training movement inan inclined plane, substantially that of the line of sight,- the correctionnever exceeds the amount of trunnion tilt and therefore no excessivejrate's of movement are hit! to x-l t.

- Referring particular the draw;

ings, the director consists of a I turntable 'I To overcome these defects a third movement was provided as illustrated in the well known Scari! ring, which was mounted on a base movable intrain and which carried'a bail on which was mounted the gun. Thegun was capable of movement in elevation and train relative to the bail. Y

Another form of so called universal gun mount was devised and was disclosed 'in- Henderson Patent No. 1,693,712 in which a third or 'crOSS' level movement "was provided between the train and elevation movements. However, the setting of the sights in this system was diillcult mounted on some solid part. or the ship where a clear and unobstructed view of the. targetmav be obtained. .Thetable .l.is.trainedf about its vertical axis by crank zfgears. 8, shaft. and

gear 5 that meshes withnteeth 6 oils. ring "gear.

surrounding. the table. Corrections in. train for v j offsetting the gun from the director maybe. made by turning hand-crank 1 and shalt 8. Shaft 8 together withshaft 9, connected to gears 3. are connected to diflerential 1,0,,tbe output of which is-connected to transmitterll. Trans: mitter: ll .transmitsto the gun receiver l2 the desired train anglesor trainorders bymeans of The inclucable I3. The values of train at the receiver is indicated by a dial I4 connected to shaft III.

The gun mount is trained by crank I1 through shaft I8, gears I8, shaft 28 and gear 2|, which meshes with teeth 22 of a ring gear surrounding the turntable I8. It is known that the table I8 is properly trained by matching the pointer 23 secured to shaft l8 with the dial I4.

The director sight 24 is moved in elevation by its being mounted on the shaft 28 which turns for traverse in bushing 28 which is rigidly secured to the trunnion 21 mounted in supports 21a. Trunnion 21 is rotated for elevating the sight about its axis by crank 28, shaft 28, worm 38, and toothed segment 8|. Corrections for gun elevations relative to the sight are applied by crank 82 turning shaft 83, whose movement is combined with that of shaft 28 by differential 84, the output of which is connected to transmitter 38.

Orders inv elevation are transmitted. from transmitter 88 by cable 38 to receiver 31. The gun 88 is brought to the proper elevation by crank 38, shaft 48, worm 4| and toothed segment 42, which is secured to trunnion 43 mounted by supports 44 on the revolving table I8.

The gun 88 is mounted in a sleeve 45 which is connected to a shaft 48 turning in bushing 41. Bushing 41 is secured to trunnion 43.

Traverse movement is given to the director sight 24 by crank 48, shaft 48, worm 58, and toothed segment 8| keyed to shaft 28. Shaft 48 turns in bearings in bracket 82 secured to trunnion 21. Corrections in traverse are made by crank 88 turning shaft 84. The movements of shafts 48 and 84 are combined in differential 55 the output of which, shaft 88, is fed into traverse transmitter 81.

Orders in traverse are transmitted by transmitter 81 through cable 88 to receiver 88, which is mounted on a bracket 88 secured to the trunnion 48. The traverse orders are made visually available to the traverse operator at the gun by dial 8| connected to the output shaft 82 of the receiver 88.

' tial 8| by shaft 82.

tial 8| is shaft 83, which is the output of train with gear 13, which is connected to shaft 18 geared to shaft 18. Shaft 18 is connected to the control element 88 of variable speed device 88 or other train generator.

In the-position shown in the drawings, gear 12 is in mesh with gears 13 and 14. The movement of shaft 11 applies corrections to the rate of train generation dB as previously described and at the same time, as disclosed in Ford Patent No. 1,468,712, applies corrections to the generated values B by gear 14 being connected to differen- The other input of differengenerator 88.

shaft 8 by the conventional follow-up consisting of differential 84, switch 85, motor 88 connected to a source of electrical power 81, and shafts 88 and 88. I

When shaft 11 is moved inwardly so that gear 12 engages gear 14 only, the 'value of train is changed without changing the rate of generation of train and when gear 12 is moved to the position indicated by dotted lines, it meshes with gear 15 only and direct manual control is had through shaft 88, shaft 4, gear 5, and teeth 8.

As described in connection with Fig. 1, shaft 8 is connected to transmitter II through differential I8, the other'input of which is shaft 8 by which deflection spots in train may be added in the conventional manner.

For the generation of elevation values, shaft 88, to which crank 28 is attached at one end, has connected to its other end the gear 8| which is adapted to be shifted to any one of four positions: (1) to mesh with gear 82 only, (2) to mesh with gears 82 and 83, (3) to mesh with gear The gun 38 is moved in traverse by crank 83,

shaft 84, worm 88 and toothed segment 88 which is keyed to shaft 48. Shaft 84 is Journaled in a bearing in bracket 88 and carries pointer 6|a which cooperates with dial 8|. It is by keeping pointer 8Ia matched with dial 8| that the gun is kept in the desired traverse position.

Fig. 2 shows a director in more detail than in Fig. 1 and includes numerous aids for the operators such as a mount for a range finder 81, variable speed devices 88 and 88 for driving the mount in train and elevation with controls for setting the rates of the variable speed devices, and automatic mechanism for moving the director sight 24 in traverse. This mechanism consists essentially of a level gyroscope 18 and a converter or' cross level corrector 1| for determinlng the traverse value. A connection from the level value of the level gyroscope continuously modifies the elevation value for level. Referring particularly to Fig. 2, the orders in train are generated, corrected, spot corrections applied, and transmitted to the gun by transmitter II and cable I3 as follows:

v Train hand crank 2 is connected by gear 12 (1) to gear 13 only, (2) to gears 13 and 14 (as shown), (3) to gear 14 only, or (4) to gear 15 only, according to the axial position in bearing 18 of shaft 11 to which gear 12 is secured.

Gear 12 in its outer position (1) is in contact 88 only, or (4) to mesh with gear 84 only. In the first position gear 8| drives gear 82 and shaft 88 which is connected to the control element 86 of variable speed device 88. The output of the variable speed gear 88 is shaft 81 which is connected to one input side of differential 88. In the second position, gear 8| engages gears 82 and 88, which latter gear is connected by shaft 88 to the other input side of differential 88. It will be seen that in this position shaft 88 applies corrections to the rate of generation of elevation dA as well as applies corrections to the values of elevation A.

In the third position gear 8| engages gear 83 only and applies corrections to the values of elevation. In the fourth position gear 8| engages gear 84 and provides a direct manual control of the director sight in elevation through shaft 188, gears I8I, shaft I82 and toothed seg- The power for turning the driving plates of the variable speed devices 88 and 88 is furnished by constant speed motor I83 through shafts I84, I88 and 488, the rotation of whichrepresents time 3. Provision is also made to change the rate of generation of train and elevation by movement.

the hand cranks when connected thereto by'the axial position of shafts 11 and 88, respectively.

In explaining the generation of the traverse values, reference is made also to Fig. 3.,which is a schematic diagram of Fig- .2 showing'the details of the converter II and its cooperation with other mechanisms. For simplicity, certain structures have been omitted from Fig. 3 such as the mechanism for turning the director turntable, the mechanism for controlling the rates of elevation and train by a single shaft, the mechanical mounting of the director sight and the range finder, etc. v

The output of differential 98 is the corrected generated elevation from the horizontal A and is represented by the rotation of shaft I I4. When there is relative motion between the platform on which the director sight is mounted and the horizontal, the elevation of the sight plane above the deck (Es) is equal to the elevation angleA plus the level angle L. The level angle L is the angle between the horizontal and the plane of the deck in the elevation plane. The generation of the level angle L by a gyroscope is well known in the art. Thelevel angle L, represented by the rotation of shaft H5, is combined with the elevation angle A by differential H6, the output of which, shaft IIBa, represents (Es) and is connected to shaft I02 by shaft I02a. For power to drive shaft I02 when gears 9| and 84 are disconnected, a motor III is connected to drive shaft I02a, motor vII'I is con-.-

nected bycables IIB to the level gyro 10 such for the time of night of the projectiles. The

that when the output (Es) of the motor-Ill is; f

combined with the elevation angle A in differential He, the rotation of. shaft II5 is;compared;-lwith the actual level value to operate a control I which actuates the motor II'I untilthe'flevei' values are equal.

Shaft I02 is-conne'cted-tothei elevating segments 2|, whichare mounted for" rotation on the supports 21a. The slght24andthe range finder 61 are thereby alitomaticaily elevated to the angle v Shaft I02 is connected to shaft 29 which as described in connection with Fig. 1 is the equivalent of shaft I02 of Figs. '2 and 3, The motion of shaft 29 and therefore of shaft I02 is combined in differential 84 with the motion of shaft 33, representing corrections to gun elevation. The output of differential 34 is connected to the transmitter 35 by a shaft 24a.

It will be recognized by those skilled in the art of correcting for trunnion tilt or cross level, that the correction (Tz) necessary to be applied as traverse may be expressed in the equation tan'Tz=tan z sin Es (1) and since both T2 and Z-are small angles the approximation Tz=Z sin Es (21 is satisfactory for all practical purposes, in which both Ta and Z may be expressed in degrees or in any other unit of that measure. Cross level Z is the angular tilt ofthe deck about a line lying in the deck and perpendicular to the elevation trunnions 21.

The value of Z is obtained from a conventional cross-level motor II! controlled by the gyro I0 mechanically or by cables I20 (Fig. 3). The value of Z is represented by the rotation of shaft I2I. Provision is also made to generate the value of Z by crank I22 connected to shaft I23 which may be connected to shaft I2I by gears I24. The shaft I2I is thereby turned until the cross-level sight I25 connected to shaft I2I by worm and gear I28 is on the horizon and is kept there.

The unit for solving Equation 2 is a conventainedby the convention jinputs are-the rate of change of deflection, shaft 1 5 wje'gand range" or time of high tional single component solver with its conventional differential I2I-in which the length of the transmitted to shaft I29. Associated withshaft' I29 are the conventional follow-up motor I30,

differential I3I, switch I32and driven shaft I33,

whose motion is identical with that of shaft I20. Shaft I33 is connected to shaft 49 which is geared to the traverse segment 5| of the director sight 24 and the traverse segment I35 of range finder 61, which is mounted in position identical with director sight 24.

In Fig. 3 are shown the details for generating and applying corrections to train and elevation range as connected to the variable scale of the range finder is represented by the rotation of shaft I36. To obtain the motion of shaft I38 from a motion that will be in direct proportion to the range, a range, converter I31, such as described in Ford Patent No. 1,526,538, is connected to shaft I36, The motion of the input of the rangeconverter, shaft I38, is in direct proportiontdztherange or maybe made in direct proportion :t'oflthe timev of flight. 1 Provision is made tocrajnk in'the-irange'io timeof flight mechani ally bashes-us" The 'computed correcti i'nf ideiiection is oboinputer I40 whose shaft'fflu. The

output of the computer 1I40; represented by the rotation' of' shaft I 4I,'is-combined;fwith the rotation of shaft-9 by differential I01;-p'reviously referredto.

Spot corrections in train may be added by turning crank I44 and shaft I45, connected to differential I48 inserted in shaft 80. The compass course of the ship may also be added by this or similar mechanism to convert the angles of train from true to relative bearings.

The computed correction in elevation is obtained by the conventional computer I41 whose inputs are the rate of change of elevation, represented by the rotation of shaft 85, and the range or time of flight, represented by the rotation of shaft I30. The output of this computer, shaft I40, is connected to shaft 33 and is thereby combined with the rotation of shaft 29 by differential 34, previously described.

Instantaneous values of the various factors represented by therotation of various shafts may be obtained by a worm gear in mesh with teeth on a dial cooperating with a reference line. These mechanisms are indicated generally throughout the drawings by the numeral I49.

It is obvious that various changes may be made by those skilled in the art in the details of the embodiment of the invention disclosed in the drawings and described above within the principle and scope of the invention as expressed in the appended claims.

I claim:

1. An anti-aircraft gun control system comprising, in combination with a gun mounted for angular adjustment about train and elevation axes with respect to an angularly movable reference plane, said gun being also mounted for angular adjustment about a traverse axis, a director including a sighting device mounted for angular movement in train about an axis perpendicular to said plane and in elevation about an axis parallel to said plane and in transverse about an axis perpendicular to a second plane including the elevation axis and the line of sight, means to apply corrections to the sighting device about the traverse axis to compensate for angular movement of the elevation axis due to angular movement of the reference 7 plane, and means to transmit to the gun the angular positions of the sighting device about the three axes to direct the adjustment of the gun about its corresponding axes.

2. An anti-aircraft gun control system comprising, in combination witha gun mounted for angular adjustment about train and elevation axes with respect to an angularly movable reference plane, said gun being also mounted for angular adjustment about a traverse axis, a director including a sighting device mounted for angular movement in train about an axis perpendicular to said plane and in elevation about an axis parallel to said plane and in traverse aboutv an axis perpendicular to a second plane including the elevation axis and the line 01' sight, means for measuring the angular movement of the elevation axis relative to the horizontal,

means actuated by themeasuring means for ad justing the position of the sighting device in traverse, and means to transmit to the gun the angular positions of the sighting device about the three axes to direct the gun about its corresponding axes.

3. An anti-aircraft gun control system comprising, in combination with a gun mountedior angular adjustment about train and elevation axes with respect to an angularly movable reference plane, said gun being also mounted for angular adjustment about a traverse axis, a

director including a sighting device mounted for, angular movement in train about an axis perpendicular to said plane and in elevation about I an axis parallel to said plane and in traverse about an axis perpendicular to a second plane including the elevation axis and .the line ofv sight, means for measuring the angular movement of the elevation axis relative to the its corresponding axes.

RAYMOND E. CROOKE.

adjustment or the I 

